Rollers for conveyors



y 12, 1959 s. HALBRON 2,886,156

ROLLERS FOR CONVEYORS Filed Dec. 19, 1957 s Sheets-Sheet 1 May 12, 1959 s. HAL'BRON ROLLERS FOR CONVEYORS.

3 Sheets-Sheet 2 Filed Dec. 19, 195'? a. q u t {Man/r01? 5 965 HAL Baa/v May 12, 1959 s. HALBRON ROLLERS FOR CONVEYORS I5 Sheets-Sheet 3 Filed Dec. 19, 1957 E y 0w, 7 r0 7 Mm M 9 92% KN m V a n \N WV c l trl ns-v i v .Vi wed in a general aspect, theinvention is embodied quired me hani a tren th sl b am mammals a v t i Acqo di o ail-nth. sQn tmc q alfq mp the i l ma eria t qrm ng a 1 Que; t a d. a f$he 1 an fthe bracin a e ted. wi e e di s a m iedl thebra in t Pro de not er bearina nrfale pposi ely lqcat sl. t t

n a a.

onwhich thecasingis abutted nb dy f the rolle a anti.

Un States aten c The presentinvention relates. generally to rollers for 15 conveyors and? particularly. for belt conveyors.

Such rollers. are usuallymad e of metal s o lthat their weight is fairly heavy and the energy which] is required for starting and drivingthem is not proporltional tosthe load being conveyed,

objec of th n tion s o pro ide a e or improved roller for a conveyor which is altogether light i an ;suificiently strongforproperly withstanding mechaniintaconveyor. roller, comprising a cylindrical envelope orl g sustain d by at. least two supporting elernen ts fm debf. ap l lm terial. n whi h jeicrmei re sse f sommpda n be jrinssl Whis re h p te l PQi Why a; ac ng t b also inedeof Plas ic ma a ial hmugh. wt ehtl e ro len' tt i s ga e 'f if el dta in According to a suitable constructional forrn of the P ll n mou ded by he n ent q h iffid "a enve 35 q a ng, s ppo ed. y at eas tw membe inade of a, plastic material inwhich arefor ed outwardly opened; cesse adapt dtoreceive bearings H tected by a tightcoyering washe t, m b sbeing a eidn i ll hs he ex t nse Q2 2 r mv on casin anihu u made vision oft e. brac n tu w iqhj e l a a e i fslr a a we: ro ler a ai 1 1E hall l a he, Whi an he. inne s i f th w e-b t e talle e roller, shaft t is p ovided with at d r e uin a rect an qsitiq h i nnp a e ha a eripheta an e i unin t H nber r .gei hylr d l' st uts and. nit

bly nriectedf to sit roller casing.

25 upon its"; shaft. Bracing discsjor fins aiej advantageously en enei tha rq ler n s i Z ..d ai la i f'lt r t s e x v r t lem nts ai u ab t n elelant .b inai e l o pa a 2,886,156 Retente May 2, 1.9.52

visionof threeakially offset bearingzones adjacenteach xt em y e l e Prmi s Pe i t n lli i' actionfto be obtained. The lubricating grease is held in the case made up of the two cast ha ltshells so thatthe roller, can run fora verylongtime without requiring -maintenance or overhaul. The end plate hasacentral aperture through which the roller shaft is engaged, the

clearance being minimurnithe amoresoas aj sealinghp and a groove are provided. A narrow gapisjleft between said aperture and the adjacent bearing surface for'hdefining in said end plat-ea dust-collecting chamber it; any dust that may have penetrated through said aperture,

the particular shape of said. bearing surface preve ting any penetrationofdustinto' the case. i

A still further, object of the invention is to provideja roller-whose casing forming its body has adouble lconicity and its bore presents a slight taper frorrifitsniiddle portion toward its, extremities. Such double co crty precludes any undue disengagement of the end plates responsive to the side. strains which bear a. upon the roller whil Performing automatic; centering of the roll er casing yided lengthwiseof the roller for properly holding up therollerlcasin with respect to the brac ng tubewhrle chemical. stre h Qf e s e ly I E i v v v an m' l b u ab ma am i jec i ou ing I 1 w git of the. roller is kept down within reason le 1i. T heas em lx s nq 'fi s tak n l count those strains which hear I upon the severalelemerits for imparting it the" desirable mechanical strength.

In the manufacture of. rollers for socalled ftrans- .irollers" i.e. conveyors rnade up ot aplnrality ofcl selly adja en p a l olle sform n i w r "a lling" E? a face, also in the manufacture of. jockey r oll ers forfthe r r c jot dr in h co ey n elthhefe i p tions of the rollers may be so constructedfas to pertnit interconnection thereof in bUtt tO-butt or. plush" re la- 'tion fthereby making it possible to manufacture rollers offairly considerable length exceeding the size of rollers "made by a mer st n p oc sse mech me strengths of elementary rollers are then so tcoinhiri ed as T to, fulfil the conditions that. are necessary ineach instance. I With thes n s1lh. i s n ew-3'5 W ldentally. appear hereinafter, the invention. comprises the novel constructionand combination of that will be now describedwith reference to the accornpanying drawing mp y he a e nd rm n a P t o the present disclosure and wherein:

Eigure 1 is a partial axial sect'on 1 view of aroller con- 9f he inten- Eigures 2 to 6 inclusive are partial perspective views showing the several elements of which the roller is made p invention;

Figure 8 is a view similar to Fig. 7 but showing; a still t further constructional form.

Figure 9 is a perspective view drain to a smaller scale of a modification of the bracingtube fitted with longitudinal supporting fins.

Figures 10 to 12 are transverse sectional views showing three possible constructional forms of a roller shaft rrrade of reinforced plastic material. l

.. Io half shell so s to ensure proper hold thereof 70 1 L v i I a l in. erfectiy concer o p0 i n with res ct th in Figure 13 1s a front VleWOf a supporting dlSC.

Figure 14 is a longitudinal sectional view'drawnto a smaller scale showing the double conicity of the roller g 'In the showing of Figs. l'to 6 inclusive, the reference .1 designates the envelope or casing forming the body of the roller whichis preferably made of a suitable plastic material. The end edge'surfaces ofthe casing 1 which has a diameter: A-B are indicated at 2. Its thickness islchosen so asto match the mechanical strength to be obtained, Adjacent each end the roller'casing contains a hub member 3 made of a suitable plastic material so shaped as to define anoutwardly opened recess 4 and.

having'a central bore 5 in which is held in push fit relation a bracing tube 6 also made of a plastic material, said tube 6'interconnecting the two end hub members of the :roller. Through the tube 6'is engaged the shaft 7 about which the roller can rotate owing to a ball bearing 10 the inner race member 12 of which is mounted upon said -shaft. The ball bearing 10 is fitted in the recess 4 and is protected from the outside by a washer 11 which performs a sealed closure. .fined betweenthe roller casing 1 and the bracing tube 6. flt vwill be understood that such a roller is particularly light while the mechanical combination between the casing land the bracing tube 6 provides the required mechanical strength for withstanding the strains exerted by An annular space 8-9 is dethe conveyor band or belt to be obtained;

Inthe showing of Fig. 7, the roller casing is designated of the bracing tube 26. Said hub member forms a bearjing surface 28 for the shaft 27. The rim portion 29 of said half shell 23 has a shoulder 31 for receiving a cone- 7 .sponding shoulder on the rim portion 32 of the other half shell 24. Said half shells may be united together in any appropriate fashion, for example by being glued together ;for.forming a case accommodating the bearing 30 whose Q innerrace member is abutted against a shoulder 33 on the shaft 27, while its outer race member is applied against abutments 34 carried 'by the half shell 23. Another -..shoulder'35 on the shaft 27 delineates the bearing 30 on "the other side. surrounds the shaft 27 while providing a further smooth bearing surface and is provided (as shown) with inner grooves which may be either circular or helical. ,The end face of the rim portion 29 of the helf shell 23 is furthermore provided with a relatively deep groove 37 The hub member 36 of the half shell 24 into which is frictionally held the end of a skirt member 39 integral with a supporting end plate 38 of circular shape whose flange 4lrwhichis connected to the skirt member 39 by reinforcing struts 40. serves as an abutment element for the roller casing 21. The bottom 42 of the end, plate 38 is provided with a central aperture through which is engaged the end 43 of the shaft 27. A lip 44 on the periphery of said aperture cooperates with a circulargroove in the, shaft 27 for performing as tight 2. sealing action as possible.

As shown in said figure, spaced supporting discs 45 are provided lengthwise of the roller for increasing its mechanical strength. I

- respect to the shaft 27 and with respect to the half shells that form the case, thereby ensuring proper hold in position. The case made up of a pair of half shells constitutes with the supporting end plate 38 a rigid assembly .iWhiCh ensures a perfect centering of the roller casing.

" the particular shape of the half shells and the supporting plate and the connection performed by the bracing tube provides a high mechanical strength of the assembly in spite of its small weight. All the parts of the rollers are so formed as to lend themselves to injection casting of plastic materials.

The casedefined by the two half shells 23, 24 may be initially filled with lubricating grease. The latter cannot ooze out owing to the provision of grooves in the hub member 36 of the half shell 24, so that the roller may operate for a prolonged time without any need for upkeep or overhaul. Dust or other extraneous matter which may penetrate through the aperture in the supporting end plate 38 is subjected in the interval between the bottom of said plate 38 and the hub member 36 to the effect of an electrostatic field due to the nature of the parts that are made of a plastic material. This attracts and fixes inversely ladendust toward the periphery of the collecting chamber'defin'ed by said plate 38, the skirt member 39 and the half shell 24. Therefore such dust cannot reach the bearing 30.

In the constructional modification shown in Fig. 8, the roller casing 31 has a double conicity as clearly visible in Fig; 14. The middle portion 52 is the narrowest one and its bore is flared towards both ends as shown at 53, 54. Consequently, the supporting discs have gradually increasing outer diameters outwardly from the middle of the roller. A disc of the type used, as seen infront'face on Fig. 13, includes a pair of ring members 55, 56united by 'a' web portion 57. The double conicity of the roller casing ensures 'a'perfect centering of the roller on 'the shaft and prevents any escapement with respect to the supporting end plates. Actually any axial effort exerted upon'the roller casing having for its tendency to disengage the same from a supporting plate is compensated'for by the wedging effect exerted upon the other end'of the roller casingon the other supporting end plate.

' 'Ring members 58 are provided about the half shell 23 for constituting an additional rest for the roller casing. The latter may be also supported from the bracing tube 5 26, by radially extending fins 59 extending over the whole .or a portion of the length of said bracing tube.

Generally speaking the roller shaft 27 is made of steel but it may be also made of a plastic material, which itself As shown in Figs. 10 to 12, suchcore may have for example a cross-shaped transverse section as visible at 60 or flutes as shown at 61 or a square cross section as shown at 62.

Minor constructional details may be modified without departing from the scope of the appended claims.

What is claimed is:

1. A roller for a belt conveyor comprising a stationary supporting shaft, a cylindrical casing made of a plastic supporting the belt, supporting end plates provided adjacent each casing end and'having a flange to whichsaid casing is abutted, cases connected to said end plates, each case-being made up of a primary inner half shell and a secondary outer half shell, said shells being made of cast plastic partsand connected to each other, hearings in said cases and interposed between the case wall and the shaft, each primary and each secondary half shell having a hub member closely surrounding said shaft for forming a bearing surface, the bearing surfaces on said respective half shells being arranged on the opposite sides of said bearing, and a bracing tube interconnecting the twocases and adapted freely to rotate about said shaft.

2. A roller for a belt conveyor according to claim 1,

2 wherein the hub member of the secondary outer half shell has grooves surrounding the shaft for forming a grooved bearing surface.

3. A roller for a belt conveyor comprising a stationary supporting shaft, a cylindrical casing made of a plastic supporting the belt, supporting end plates made of. a plastic arranged adjacent each casing end andhaving a essence flange to which said casing is abutted, cylindrical skirt members extending from said end plates inwardly of said flanges, reinforcing struts interconnecting said skirt members and said flanges, cases connected to said cylindrical skirt members, each case being made up of a primary inner half shell and a secondary outer half shell, said shells being made of cast plastic and mutually intercorr nected, bearings in said cases interposed between the case wall and the shaft, each primary half shell and each secondary half shell having a hub member closely surrounding the shaft for forming a bearing surface, the bearing surfaces on the primary and secondary half shells being arranged on the opposite sides of the bearing, and a bracing tube interconnecting the two cases and adapted freely to rotate about the shaft.

4. A roller for a belt conveyor comprising a stationary supporting shaft, a cylindrical casing made of a plastic material supporting the belt, supporting end plates adjacent each casing end and having a flange to which said casing is abutted, apertures on said end plates for the passage of the shaft, a lip bordering said apertures in the end plates, a groove in the shaft in registration with said lip for providing a sealed contact, cases connected to said end plates, each case being made up of a primary inner half shell and a secondary outer half shell, both shells being made of cast plastic parts and being mutually interconnected, bearings in said cases interposed between the case Wall and the shaft, each primary and each secondary half shell having a hub member closely encompassing the shaft for forming a bearing surface, the bearing surfaces on the respective shells being arranged on the opposite sides of the bearing, the bearing surface of the secondary half shell being slightly offset from the aperture in the adjacent end plate for defining a dust-collecting chamber between said shell and said secondary half shell, and a bracing tube interconnecting the two cases and adapted freely to rotate about said shaft.

5. A roller for a conveyor belt according to claim 4, wherein cylindrical skirt members extend from the end plates, the cases which accommodate the bearings being fixed to said skirt members, reinforcing struts interconmeeting said skirt members to the flange on the end plates, the hub member of the outer secondary half shell of each case having grooves surrounding the shaft for forming a grooved bearing surface.

6. A roller for a belt conveyor comprising a stationary supporting shaft, a cylindrical casing made of a plastic material supporting the belt, supporting end plates each having a peripheral flange, a cylindrical skirt member and reinforcing struts interconnecting said flange and said skirt member, said casing being abutted to the flange on the end plate, cases each of which has a primary inner half shell and a secondary outer half shell, both shells being made of molded plastic material, each primary half shell and each secondary half shell having a rim portion and a hub member, said hub member surrounding the roller shaft for building a bearing surface, a bearing mounted in each case between said half shells, shouldered portions on the rim portions of the half shells for assembling them, a fitting groove in the rim portion of the primary half shell of each case for the engagement of the skirt member of the adjacent end plate, a bracing tube interconnecting the two cases and adapted freely to revolve about said shaft, and a groove formed in the hub member of each primary half shell for the engagement of said bracing tube so that the bracing tube, the half shells of said cases, the end plates and the roller casing form a unitary assembly having a high mechanical strength.

7. A roller for a belt conveyor comprising a stationary supporting shaft, a cylindrical casing made of a plastic material supporting the belt, said casing defining an axial bore having a double conicity, the diameter of each conicity growing from the middle of the casing toward each end, supporting end plates adjacent each casing end and having a flange on which said casing is abutted, cases connected to said end plates, each case being made up of a primary inner half shell and a secondary outer half shell, both shells being constituted by parts made of cast plastic material, said half shells being mutually interconnected, bearings accommodated in said cases and interposed between the case walls and the shaft, each primary half shell and each secondary half shell having a hub member closely surrounding the roller shaft for forming a bearing surface, said bearing surfaces being arranged on the opposite sides of the bearing, and a bracing tube interconnecting said cases and adapted freely to rotate about said shaft.

8. A roller for a belt conveyor according to claim 7, wherein abutment discs distributed over the length of the roller are interposed between the casing and the bracing tube, the outer diameter of said discs growing from the middle of said casing toward its ends.

References Cited in the file of this patent UNITED STATES PATENTS 2,607,459 Ludwig et al Aug. 19, 1952 

